The present invention relates to an anchor (or connector) which can be used to fasten organic tissue in close proximity in order to afford the tissue the opportunity to heal. The anchor of the present invention can be used to anchor and clamp dense, regular and/or dense, irregular connective tissue in place in relation to bone. The anchor can also be used for cartilage transplants, i.e., for holding cartilage in fixed relation to bone, and can also be used in bone as a buttress, such as for buttress plating techniques, or to fasten pieces of bone together as a screw substitute.
As compared to the prior art, the anchor of the present invention allows a method of holding together organic tissue with minimal disruption to the biological environment or to the tissue itself. For example, prior art devices and methods customarily require a large hole for insertion of the anchoring device, causing not only structural damage to the implantation site, but also inflicting further trauma to the biological site such as generating heat, introducing further possibility for infection, and destroying bone which may be needed to help heal the repaired area. Such trauma is amplified in cases where prior art devices malfunction during the implant procedure. Hooks or screws can get stuck and further obscure the operating site or require tedious removal.
The anchor of the present invention may be very useful for applications such as anchoring ligaments or tendons when performing soft tissue surgical reconstruction, ruptured tendons, or torn ligaments, in which the surgeon wants to reconstruct or repair connective tissue with respect to the bone.
The anchoring device functions to hold together the tissue (such as connective tissue to bone) for a relatively limited time frame, e.g., six to twenty-six weeks, during which time the biological system will heal.
The anchor of the present invention can be used with advantage in many of the same applications in which cancellous screws are used in addition to applications in which traditional prior art anchoring techniques are unsatisfactory. The anchor of the present invention is far less invasive to implant than cancellous screws or hook-style anchors, i.e., the implant has a minimized mass, the insertion point is small relative to the size of the implant, and the device involves minimal removal of native tissue. In addition, the area of bone which is needed to secure the present invention can be of poorer quality than for prior art devices.
Additionally, the anchor of the present invention can be removed and minimally reangulated in order to utilize the same surgical site. Prior art devices require a large hole (relative to implant size) to be drilled in order to implant the device, and once the hole is contaminated by malfunction or misalignment of the device, it is necessary to drill another hole far enough away to achieve stability in a new location. Given the surgical context, this is extremely inconvenient.
The anchor of the present invention can be used in methods of ligament, tendon, or other tissue repair. For example, the anchor can be used for a method involving cartilage transplant and it can be used alone or in conjunction with a plate for a method of buttressing bone where the quality of bone may be questionable due to trauma or degenerative disease. The anchor may be used in methods of fixation involving connective tissue repair and replacement and may be inserted using a plunge-handle or "T" handle inserter which utilizes longitudinal travel in order to achieve rotational insertion.
Specifically, the anchor is used in ligament or tendon repair in which a pilot hole, having a diameter much smaller than the outer diameter of the helical anchor, is drilled in the cortex of the bone. The angle of implantation can be varied as necessary. The anchor is subsequently mounted or loaded into the insertion tool, threaded into the pilot hole, and screwed into the bone an appropriate distance so that the anchor head can be accessed but is not obtrusive. The ligament or tendon is attached to the anchor, such as by suturing.